Invisible, light transmissive display system

ABSTRACT

An invisible, light-transmissive display system with a light resistant material is provided. Substantially invisible, tapered, light-transmissive holes are penetrated in a lighttransmissive pattern through at least a portion of the light resistant material using a laser beam having a focal width less than the smallest diameter of the tapered holes.

CROSS-REFERENCE TO RELATED APPLICATION

This is a continuation of U.S. patent application Ser. No. 12/973,632filed Dec. 20, 2010, which is a continuation of U.S. patent applicationSer. No. 11/551,988 filed Oct. 23, 2006, now U.S. Pat. No. 7,880,131:which is a continuation-in-part of co-pending U.S. patent applicationSer. No. 11/456,833 filed Jul. 11, 2006, now U.S. Pat. No. 7,884,315,and assigned to the assignee of the present application.

TECHNICAL FIELD

The present invention relates generally to device display systems, andmore particularly to invisible, light-transmissive display systems thatbecome visible when illuminated from behind.

BACKGROUND

In the world of consumer devices, and particularly consumer electronics,there is an ever-present demand for improved appearance, improvedfunctionality, and improved aesthetics. Industrial design has become ahighly skilled profession that focuses on fulfilling this need forenhanced consumer product appearance, functionality, and aesthetics.

One area that continually receives great attention for improvement isuser displays. Providing crisp, attractive, unambiguous, and intuitivelyfriendly displays and information for the user is very important in manyconsumer products. However, as consumer products constantly becomesmaller and smaller, and in some cases more and more complex, it becomesincreasingly difficult to present and display user information in amanner that is easy for the user to grasp and understand, but is also inan uncluttered form and appearance that is aesthetically pleasing.

Much of the aesthetic appeal of a consumer product can quickly becompromised if there are too many display elements, or if too muchdisplay area is occupied by display elements that are not needed exceptat particular times. When not needed, these “passive” or unactivateddisplay elements invariably remain visible to the user, even though inthe “off” state. This is not only displeasing from an aestheticstandpoint, but it can be an annoying distraction that interferes withdetection and understanding of other display elements that need to beobserved at a given moment.

Many display elements are illuminated. Some display elements areilluminated continuously; others are illuminated only when appropriateto instruct and guide the user. Display elements that are notcontinuously illuminated can be distracting, or at least aestheticallyobjectionable, when not illuminated (when in the off state) because theystill remain visible in the display area.

For example, one typical such display element is configured fromtransparent plastic inserts that penetrate through the metallic case ofan electronic device, and are smoothly flush with the outer surface ofthe case. Oftentimes, a large number of such always-visible displayelements leads to a cluttered, confusing, and unattractive appearance.In fact, even a single such element, when not illuminated (i.e., in aninactive state), can become an unattractive blotch on an otherwisesmooth and attractive surface.

Less expensive device cases, for example, those made of opaque plasticrather than metal, are often similarly provided with transparent plasticinserts for illuminated display elements. These display elements alsoconflict with a good aesthetic appearance when they are not illuminated.

Also, prior displays using plastic or glass are less durable than metaland are more subject to breaking or cracking.

Additionally, the separate visible inserts utilized by prior techniquessometimes do not fit perfectly in the holes in which they are insertedor formed. Such imperfect fit can invite entry of liquids, dirt, and soforth, undesirably causing yet another disadvantage.

Thus, a need still remains for commercially feasible device displaysystems with improved aesthetics that unobtrusively furnish informationas appropriate but otherwise do not distract or detract from the user'sexperience or the device's performance. Preferably, selected elements ofsuch display systems would additionally become invisible in their offstates.

In view of ever-increasing commercial competitive pressures, increasingconsumer expectations, and diminishing opportunities for meaningfulproduct differentiation in the marketplace, it is increasingly criticalthat answers be found to these problems. Moreover, the ever-increasingneed to save costs, improve efficiencies, improve performance, and meetsuch competitive pressures adds even greater urgency to the criticalnecessity that answers be found to these problems.

Solutions to these problems have been long sought but prior developmentshave not taught or suggested any solutions and, thus, solutions to theseproblems have long eluded those skilled in the art.

SUMMARY

The present invention provides an invisible, light-transmissive displaysystem with a light resistant material. Substantially invisible,tapered, light-transmissive holes are penetrated in a light-transmissivepattern through at least a portion of the light resistant material. Theinvisible holes are penetrated using a laser beam having a focal widthless than the smallest diameter of the tapered holes. A summary ofcertain embodiments disclosed herein is set forth below. It should beunderstood that these aspects are presented merely to provide the readerwith a brief summary of these certain embodiments and that these aspectsare not intended to limit the scope of this disclosure. Indeed, thisdisclosure may encompass a variety of aspects that may not be set forthbelow

Certain embodiments of the invention have other aspects in addition toor in place of those mentioned above. The aspects will become apparentto those skilled in the art from a reading of the following detaileddescription when taken with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a view of a portable computer incorporating an invisible,light-transmissive display system according to the present invention;

FIG. 2A is an enlarged detail from FIG. 1 of status indicators shown man illuminated state;

FIG. 2B is a view similar to FIG. 2A in which the status indicators arem an unilluminated state;

FIG. 3A is an enlarged detail from FIG. 1 of the caps lock indicatorshown in an illuminated state;

FIG. 3B is a view similar to FIG. 3A in which the caps lock indicator ism an unilluminated state;

FIG. 4A IS an enlarged detail from FIG. 1 of the sleep indicator shown man illuminated state;

FIG. 4B IS a view similar to FIG. 4A m which the sleep indicator IS m anunilluminated state;

FIG. 5A is a bottom view of the portable computer of FIG. 1;

FIG. 5B is a view similar to FIG. 5A in which the battery statusindicator lights are in an unilluminated state;

FIG. 6A is a view of a personal music player with a surface logo in anilluminated state;

FIG. 6B is a detail from 6A showing the logo in an unilluminated state;

FIG. 7 is an enlarged view of a fragment of light resistant materialhaving an opaque outer surface and incorporating an invisible,light-transmissive display system formed according to an embodiment ofthe present invention;

FIG. 8 is a cross-sectional view of the fragment shown in FIG. 7, takenon line 8-8 in FIG. 7;

FIG. 9 is a view of a system for forming invisible holes according tothe present invention;

FIGS. 10 and 11 progressively depict the formation of the hole begunwith the system shown in FIG. 9;

FIG. 12 is a view of the structure of FIG. 8 following application of aclear coat into the invisible holes;

FIG. 13 is a view of the structure of FIG. 12 after finishing of theclear coat;

FIG. 14 is a view of the structure of FIG. 13 provided with a structuralplug;

FIG. 15 is a view of a structure similar to that in FIG. 13 but havingindividual lights for each of the holes;

FIG. 16 is a view of a structure having a TFT layer aligned with theindividual holes;

FIG. 17 is a view of an embodiment of the present inventionincorporating invisible holes that are outwardly directed;

FIG. 18 is a view of an embodiment of the present inventionincorporating invisible holes that are inwardly directed;

FIG. 19 is a view of an embodiment having a light sensitive receptorbehind the invisible holes;

FIG. 20 is a view of an embodiment of the present invention configuredas an invisible proximity detector;

FIG. 21 is a view of an embodiment of the present invention configuredas an invisible button;

FIG. 22 IS a view of an embodiment of the present invention configuredas an invisible slot;

FIG. 23 is a cross-sectional view of the invisible slot shown in FIG. 22taken on line 23-23 in FIG. 22;

FIG. 24 is a cross-sectional view of the invisible slot shown in FIG. 22taken on line 24-24 in FIG. 22; and

FIG. 25 is a flow chart of a process for manufacturing an invisible,lighttransmissive display system in accordance with an embodiment of thepresent invention.

DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS

The following embodiments are described in sufficient detail to enablethose skilled in the art to make and use the invention. It is to beunderstood that other embodiments would be evident based on the presentdisclosure, and that process or mechanical changes may be made withoutdeparting from the scope of the present invention.

In the following description, numerous specific details are given toprovide a thorough understanding of the invention. However, it will beapparent that the invention may be practiced without these specificdetails. In order to avoid obscuring the present invention, somewell-known system configurations and process steps are not disclosed indetail.

Likewise, the drawings showing embodiments of the system aresemi-diagrammatic and not to scale and, particularly, some of thedimensions are for the clarity of presentation and are shown greatlyexaggerated in the drawing FIGS.

Similarly, although the views in the drawings for ease of descriptiongenerally show similar orientations, this depiction in the FIGS. isarbitrary for the most part. Generally, the invention can be operated inany orientation. In addition, where multiple embodiments are disclosedand described having some features in common, for clarity and ease ofillustration, description, and comprehension thereof, similar and likefeatures one to another will ordinarily be described with like referencenumerals.

For expository purposes, the term “horizontal” as used herein is definedas a plane parallel to the plane or surface of the display, regardlessof its orientation. The term “vertical” refers to a directionperpendicular to the horizontal as just defined. Terms, such as “above”“below” “bottom” “top” “side” (as in “sidewall”) “higher” “lower”“upper”, “over”, and “under”, are defined with respect to the horizontalplane. The term “on” means that there is direct contact among elements.

The term “system” as used herein refers to and is defined as the methodand as the apparatus of the present invention in accordance with thecontext in which the term is used.

Referring now to FIG. 1, therein is shown a portable computer 100 havinga housing base 102 that supports a keyboard 104 having keys 106, atouchpad 108, a release latch 110, and so forth. The housing base 102also supports conventional components (not shown) such as a powersupply, a microprocessor (“CPU”), a computer memory, a hard drive(“HD”), an optical disk drive (“ODD”), and so forth. A display 112 ishingedly attached to the housing base 102, and when closed is retainedin place by the release latch 110.

The portable computer 100 has several status indicators according to thepresent invention, as will be described in further detail below. Thesestatus indicators include, for example, a caps lock indicator 114, asleep indicator 116, status indicators 118, a power button 120, and soforth. The caps lock indicator 114 is located in the caps lock key 122of the keyboard 104 to indicate when the caps lock function of thekeyboard 104 has been engaged. The sleep indicator 116 is located in therelease latch 110 to indicate when the portable computer 100 has beenengaged in a sleep mode. The status indicators 118 may be used toprovide information concerning the status of any function or activityassigned thereto, for example, wireless link status, video camerastatus, low battery, battery charging, hard drive activity, and soforth. Similarly, the power button 120 can be illuminated to indicatethat the computer is powered on, or may be illuminated upon opening thedisplay 112 to assist in locating the power button 120, and so forth.

In prior computer configurations and designs, these various statusindicators are ordinarily visible to the user in both the activated (or“on”) and the inactivated (or “off”) states. In the on state, anindicator will characteristically be illuminated continuously orperiodically (e.g., cyclically), sometimes with a particularinformational color according to the status that the indicator isreporting. In the off state, the indicator will typically be darkened(inactivated or unilluminated), but unfortunately (in manycircumstances) can nonetheless still be seen. In the off state,therefore, the indicator often distracts and/or spoils the aesthetics ofthe portable computer 100.

In contrast, it is believed that a majority of consumers would find theportable computer 100 to be more attractive if status indicators of thissort became invisible in the off state. Of course, it will also beappreciated that there are other circumstances in which an indicator,such as a logo, would preferably remain visible even when in the offstate, and circumstances of that sort are also addressed hereinbelow.

Concerning status indicators that would ideally not be visible (i.e.,would disappear) in the off state, a principal difficulty faced byprevious techniques is that such status indicators are ordinarilylocated in a partially or completely opaque display surface area. Forthe status indicator to function, therefore, the surface is interruptedat the status indicator location so that the light from the statusindicator can be externally visible to the user. The consequent visiblediscontinuity in the appearance of the surface is therefore alwaysvisible to the user, whether the indicator is on or off.

There have been previous efforts to reduce or eliminate the visibilityof such status indicators when in the off state. One such priortechnique preserves the integrity of the display surface by reducing thethickness of a metallic display panel from the rear in the region orarea of the status indictor. The thickness is reduced until the metallicdisplay panel actually becomes light-transmissive. When light is thenshined on the rear or back side of the metallic display panel, it passesthrough that region and becomes visible on the opposite (outer or front)side of the metallic display panel. Thus, by thinning the metal onlyfrom the back side, the opposite side of the metallic display panelremains smooth, untouched, and uninterrupted. As such, the statusindicator region in the off or unilluminated state cannot bedistinguished and is invisible from the unmodified outside surface ofthe metallic sheet.

In one implementation of this technique, a matrix of holes was formedfrom and into one side (e.g., the “back side”) of a metal sheet nearlyto the surface of the other side (e.g., the “front side”). For example,using laser ablation on an aluminum sheet, the holes were formed fromthe back side of the metallic aluminum sheet until there was a thicknessof metal remaining at the front side on the order of only 12-20 nm. Thematrix of holes was configured in the shape of a desired indicator, suchas an arrow. The very small thickness of metal remaining at the end ofeach hole at the front surface of the metallic aluminum sheet allowedlight to pass outwardly through the front surface of the sheet when thelight was shined into the holes from the back surface thereof.

Unfortunately, such a reduced metallic thickness technique is veryexpensive due to the extreme precision required for the laser ablation(e.g., using a femtosecond laser) and the need for metallic sheetshaving a very even thickness and very even and flat surfaces. The needto have a perfectly flat metallic sheet can be somewhat mitigated byusing a camera or other light-detecting device that is directed at thefront surface of the metallic sheet in the vicinity where the holes arebeing laser-drilled from the back side of the sheet. The camera thendetects light from the laser just as the remaining metal at the end ofthe hole becomes light transmissive. Upon detecting the desiredintensity of light from the laser, the laser drilling process can thenbe terminated. However, this is a sensitive process and is veryexpensive.

Such reduced metallic thickness, light-through-metal status indicatorsare also fragile due to the very thin, easily damaged metallic membranesat the ends of the holes at the front surface of the metallic sheet.

Another disadvantage is that the amount of light transmitted is verysmall. For example, at 22 nm thickness of aluminum, only about onepercent of the light is transmitted; at 12 nm approximately six percentis transmitted. Thus, intense illumination is needed on the back side ofthe metallic sheet to provide an acceptably visible status indication onthe front surface.

The systems of the present invention overcome the numerous disadvantagesof previous techniques. They also provide new versatility, options, andcapabilities not achievable with previous techniques.

Referring now to FIG. 2A, therein is shown an enlarged detail from FIG.1 of the status indicators 118 according to the present invention. Thestatus indicators 118 are illustrated in the on or illuminated andvisible state.

Referring now to FIG. 2B, therein is shown a view similar to FIG. 2A inwhich the status indicators 118 are in the off or unilluminated state.As can be seen, the status indicators 118 in the off state have becomeinvisible. The surface of the display 112 in which the status indicators118 are located is smooth, continuous, uncluttered, and uninterrupted.

Referring now to FIG. 3A, therein is shown an enlarged detail from FIG.1 of the caps lock indicator 114 according to the present invention. Thecaps lock indicator 114 is illustrated in the on or illuminated andvisible state.

Referring now to FIG. 3B, therein is shown a view similar to FIG. 3A inwhich the caps lock indicator 114 is in the off or unilluminated state.As can be seen, the caps lock indicator 114 in the off state has becomeinvisible. The surface of the caps lock key 122 in which the caps lockindicator 114 is located is smooth, continuous, uncluttered, anduninterrupted.

Referring now to FIG. 4A, therein is shown an enlarged detail from FIG.1 of the sleep indicator 116 according to the present invention. Thesleep indicator 116 is illustrated in the on or illuminated and visiblestate.

Referring now to FIG. 4B, therein is shown a view similar to FIG. 4A inwhich the sleep indicator 116 is in the off or unilluminated state. Ascan be seen, the sleep indicator 116 in the off state has becomeinvisible. The surface of the release latch 110 in which the sleepindicator 116 is located is smooth, continuous, uncluttered, anduninterrupted.

The status indicators 118, the caps lock indicator 114, the sleepindicator 116, and other desired display patterns that disappear in theoff state, form “ghosted field” display patterns that appear anddisappear (like ghosts) when turned on and off. As explained in greaterdetail hereinbelow, such invisible, light-transmissive display systemscan be provided for viewing at an outer surface of a light resistantmaterial. Such a light resistant material may be, for example, asubstantially opaque material such as metal, or a light-absorbing buttranslucent material such as colored plastic, or a coated or paintedmaterial, or material of other appropriate composition andconfiguration. As used herein, therefore, “light resistant” refers tosome degree of light attenuation, up to and including complete opacity.

Invisible holes are then penetrated in one or more desiredlight-transmissive display patterns through at least a portion of thelight resistant material to provide the ghosted field display patterns.

Referring now to FIG. 5A, therein is shown a bottom view of the portablecomputer 100 of FIG. 1. Accessible on the bottom 502 of the portablecomputer 100 is a battery pack 504 having battery status indicatorlights 506. In one embodiment, for example, a test button 508 on thebattery pack 504 can be actuated to cause the battery status indicatorlights 506 to illuminate according to the charge state of the batterypack 504. The more battery status indicator lights 506 that illuminate,the higher the charge level of the battery pack 504. FIG. 5A illustratesthe indicator state in which all five of the battery status indicatorlights 506 are illuminated, showing a fully charged battery.

Referring now to FIG. 5B, therein is shown a detail from FIG. 5A inwhich the battery status indicator lights 506 are in the off orunilluminated state. However, although the battery status indicatorlights 506 are off, they have not become invisible. Rather, in somesituations, it may be desirable for a status indicator to remain atleast partially visible when in the off state. For example, the batterystatus indicator lights 506 number five such indicators. Sometimes,actuation of the test button 508 will cause only some (or none) of thebattery status indicator lights 506 to illuminate, thereby indicating acorresponding partially charged (or discharged) state for the batterypack 504. In such a case, it can be desirable for the remaining batterystatus indicator lights 506 that are in the off state to be visible sothat the user can easily see what proportion is illuminated. Thus, asillustrated in FIG. 5B, the battery status indicator lights 506 are allin the off state but remain visible.

The persistent visibility for the battery status indicator lights 506(or any other desired status indicators) when in the off state may beachieved, for example, by providing a different surface treatment on thesurface where the status indicators are located, or, for example,heating the surface during formation of the status indicatorssufficiently to discolor or even slightly burn the surface, to achievethe desired effect. Or, the surface may be colored such as byapplication of a paint, color, or dye in the desired pattern.Alternatively, or in addition, the status indicator through-the-surfacelight-conducting invisible holes (as explained below starting with thedescription of FIG. 7) may include additional holes of visible sizeand/or include clear coat formulations (as described furtherhereinbelow) that contrast with the surface where the status indicatorsare located. In this way, the locations and states of the indicators arealways visible, even though the principle means by which the light isactually able to emanate from the display surface (i.e., the invisibleholes) cannot be seen.

Referring now to FIG. 6A, therein is shown a personal music player 600.A logo 602 is provided as an intrinsic, visible design on a surface ofthe personal music player 600, and is shown in the on (illuminated)state. Utilizing the invisible hole technology of the present invention(explained further hereinbelow), the light from the logo 602 emanatesfrom the surface of the personal music player 600 with no visiblesource. To the unaided eye, the surface of the logo appears continuous,solid, metallic, and seemingly incapable of transmitting light. Thiscontinuous, uninterrupted and unblemished surface, which neverthelessemits light, is accordingly particularly aesthetically appealing.

Referring now to FIG. 6B, therein is shown a detail from FIG. 6A showingthe logo 602 in the off (unilluminated) state. Unlike the statusindicators of the present invention that disappear in the off state(e.g., the status indicators 118 (FIG. 2B), the caps lock indicator 114(FIG. 3B), and the sleep indicator 116 (FIG. 4B)), the logo 602, asdepicted in FIG. 6B, remains visible in the off state (like the batterystatus indicator lights 506 (FIG. 5B)).

Accordingly, depending upon the implementation of the present invention(as detailed more particularly hereinbelow), a wide variety of effectsand treatments can be provided as desired. Thus, as depicted in FIG. 6B,the unilluminated logo 602 may be configured to appear as a logo that isetched into a solid metallic surface. Then, upon illumination of thelogo 602 from behind, light emanates from the seemingly solid metallicsurface of the logo 602, as depicted in FIG. 6A, realizing aparticularly attractive and dramatic effect.

Referring now to FIG. 7, therein is shown an enlarged view of a fragment700 of light resistant material having an opaque outer surface 702according to an embodiment of the present invention. In one embodiment,the opaque outer surface 702 is the outer surface of a metallic sheet ofaluminum. Holes 704 are formed in and penetrate through the opaque outersurface 702 to the opposite or inner side (i.e., the rear surface 804shown in FIG. 8) of the fragment 700.

The holes 704, although shown greatly exaggerated in the drawing FIGS.,are actually invisible. That is, each of the holes 704 is smaller thanresolvable by an unaided human eye. For example, the limit of resolutionfor the human eye is about 0.1 mm at a distance from the eye of 1 meter.In children, the resolution might be somewhat finer, for example, 0.04mm. Thus, depending upon the anticipated viewer and viewing distance,the holes 704 will be selected to be below the limit of resolution, andit will accordingly be understood that the term “invisible hole” refersto this upper limit. Thus, as defined herein, “invisible holes” refersto holes that are smaller than resolvable by an unaided human eye.

Conversely, it will be understood that the term “visible holes” refersto holes that are large enough to be resolvable by an unaided human eye.

As depicted in FIG. 7, the holes 704 are arranged in a pattern 706 of 37holes that form a status indicator shaped in a generally circularpattern as a circle or dot. For expository reasons, just as the holes704 are shown greatly exaggerated in size, so also is the size andarrangement of the pattern 706 greatly exaggerated. Typically, however,the pattern 706 will be large enough to be seen (when illuminated) bythe unaided human eye—such as of the size of conventional statusindicators.

In one embodiment in which the holes 704 are utilized to form statusindicators for a portable computer such as the portable computer 100(FIG. 1), the holes 704 have a diameter at the outer surface 702 ofabout 30 11 m. Center-to-center spacings or pitch between the holes 704is a nominal distance of about 200 11 m. However, the size of the statusindicator pattern itself (e.g., the pattern 706) can vary from afraction of a mm to several mm across, depending upon the actual patternthat is depicted.

Referring now to FIG. 8, therein is shown a cross-sectional view 800 ofthe fragment 700, taken on line 8-8 in FIG. 7, and showing furtherdetails of this embodiment of the present invention. In this embodiment,the fragment 700 is formed of an aluminum (“Al”) sheet that is nominallyabout 0.5 mm thick. The fragment 700 has then been machined down in thevicinity of the pattern 706 to a thickness of about 400˜-tm-500 11 m,forming a cavity 802 into the rear surface 804 of the fragment 700. Thecavity 802, which is thus opposite the outer surface 702 in the vicinityof the pattern 706, facilitates formation of the holes 704 by thinningthe thickness of the fragment 700 in the vicinity of the pattern 706.This reduces the amount of drilling needed to form the holes 704 throughthe fragment 700.

It will be appreciated, of course, that in certain situations the cavity802 can be advantageous, while in others it may not appreciably improveoverall manufacturing efficiency or speed. For example, when thefragment 700 is not particularly thick (e.g., on the order of up to 0.7mm or so of AI), the additional time for laser drilling a pattern ofholes such as the holes 704 may increase by only a few seconds to lessthan a minute. In such a case, it may be more efficient and economicalto omit the cost and delay associated with first forming the cavity 802.

In this embodiment, the holes 704 are tapered, having about a 0.33aspect ratio (i.e., the hole size at the outer surface 702 relative tothe size at the rear surface 804). Thus, the hole 704 diameter at therear surface 804 is about 90 11 m.

Referring now to FIG. 9, therein is shown an embodiment of ahole-forming system 900 for forming the holes 704 according to thepresent invention. The formation of the holes 704 is shown in the earlystages thereof, with two holes 704A and 704B formed, and laser drillingof a third hole 704C having just begun.

To form the holes 704, the fragment 700 is inverted, and formation ofthe holes is performed from the rear surface 804 using a laser 902, suchas an ultra-violet (“UV”) computer numerical controlled (“CNC”) lasertool having, for example, a 1000 picometer wavelength laser beam 904with a focal width 905 (spot size) of about 15 11 m. In otherembodiments, green lasers or YAG lasers can be used, in some cases moreeconomically, such as when larger holes (e.g., greater than about 45 11m) are being formed through the fragment 700.

The term “tapered” is used and defined herein to mean a gradualnarrowing toward one end. To achieve the tapered hole configuration, thelaser beam 904 has been configured, as just described, with a focalwidth 905 no larger (and preferably less) than the smallest diameter ofthe tapered hole that is to be formed. In one embodiment, the focalwidth 905 is no larger than substantially half the smallest diameter ofthe tapered hole. The laser beam 904 is then initially orbited aroundthe edges of the holes 704, as illustrated with respect to hole 704C,the dotted lines embraced within an arrow indicating the orbit 906 ofthe laser beam 904. The orbiting of the laser beam 904 is begun bydescribing the initial, largest hole diameter, which in this embodimentis about 90 11 m at the rear surface 804. As the hole, such as hole704C, then forms and deepens, the orbit 906 of the laser beam 904 iscorrespondingly tightened to progressively reduce the diameter of theobit 906, and thus reduce the diameter of the hole. At the conclusion ofthe hole formation at the outer surface 702, the orbit 906 has beenprogressively and continuously reduced until it is only, as in thisembodiment, about 30 11 m, which is still larger than the laser beam'sfocal width 905 of about 15 11 m.

The formation of the holes 704 is thus a trepanning operation as thelaser beam 904 “corkscrews” (cf. the arrow for the orbit 906) in atightening spiral into and through the fragment 700. The laser 902 thusperforms a tightening trepanation until the laser beam 904 exits at theouter surface 702 at the smallest diameter of the tapered hole 704.During this trepanning operation, as the laser beam 904 sweeps aroundthe edge surface of the hole 704, the laser beam 904 melts the innersurface 908 of the hole 704, leaving the inner surface 908 with a clean,smooth, mirror finish formed thereon that aides in guiding andreflecting light therethrough.

It has been discovered that the controlled formation and shaping of theholes 704 with the laser beam 904 in this manner gives the holes theparticular characteristics of having been formed using a laser beamhaving a focal width 905 less than the smallest diameter of the taperedholes. Other aspects of the holes and slots, as described furtherherein, have likewise been found to be characteristic of the manner inwhich they were formed by the laser beam.

Referring now to FIGS. 10 and 11, therein is shown the structure of FIG.9 progressively depicting the formation of the hole 704C, as justdescribed. In FIG. 10, the hole 704C has been deepened from the earlierstate shown in FIG. 9, and the orbit 906 has been reduced (tightened).In FIG. 11, the hole 704C has been completed, with the orbit 906 reducedto the diameter of the hole 704C at the outer surface 702.

Referring now to FIG. 12, therein is shown the structure of FIG. 8following application of a light-conductive filler such as a clear coat1202 into the holes 704. The clear coat 1202 may be any suitable clearor translucent coating or material, such as a clear paint or sealant,that functions as a light-conductive filler. Depending upon theparticular use and configuration at hand, such a clear coat 1202 may bewater based and cured by water evaporation, or polymer based (polymeric)and cured by ultraviolet (“UV”) light, heat curable, and so forth, as isknown in the liquid coating arts.

In one embodiment, the clear coat 1202 is a UV-curable polymeric liquidhaving a viscosity in the range of 25 centipoise. The clear coat 1202 isapplied and filled into the holes 704 by orienting the outer surface 702upwardly and placing a drop 1204 of the liquid clear coat 1202 on theouter surface 702, on top of the pattern 706, where the diameters of theholes 704 are the smallest. Gravity and capillary action, aided by theconical taper of the holes 704, then draw the clear coat 1202 into theholes 704, filling the holes from the smallest diameters thereof. Aftera time suitable for the liquid clear coat 1202 to be drawn thus into andthrough the holes 704, the clear coat 1202 is cured in the holes 704 byexposure to UV light 1208 from the rear surface 804.

In one embodiment, the application time for the clear coat 1202 can beextended, and/or the volume of the drop 1204 of the liquid clear coat1202 increased, to allow the capillary action and gravity to slightlyover-fill the holes 704 before curing, resulting in a dome 1206 of theclear coat 1202 on the inside end of each such filled hole 704. Thedomes 1206 extend convexly from the rear surface 804 and act somewhatlike a prism to gather more light when illuminated from that side (i.e.,illuminated from a light source at the rear surface 804).

After curing, the uncured remainder of the drop 1204 is removed (e.g.,by wiping with a solvent) and the tops of the cured clear coat 1202 inthe holes 704 are finished at the outer surface 702 as desired (forexample, flush with the outer surface 702).

Referring now to FIG. 13, therein is shown the structure of FIG. 12after application and finishing of the clear coat 1202 as justdescribed. The pattern 706 is now ready to be illuminated, such as by alight 1302 located opposite or within the cavity 802 and configured forproviding light to be transmitted through the holes 704 when the pattern706 status indicator is actuated to the on state.

It has been discovered that the clear coat 1202 provides severalaspects. For example, it closes and seals off the holes 704, protectingthem from ingress of water, dirt, oil, and other contaminants that mightdegrade the light transmissivity thereof. The outer surface 702 is thussecured in case of exposure to contamination. It also provides for asmooth and continuous surface, free from visible breaks and break linesin the material.

Referring now to FIG. 14, the fragment 700 has been optionally providedwith a structural plug 1402 (for example of clear plastic) inserted intothe cavity 802. A suitable adhesive, such as an adhesive tape 1404, maybe used to secure the structural plug 1402 in the cavity 802.Alternatively, another suitable backfill material may be provided, suchas a transparent liquid polymer that has been filled into the cavity 802and then cured, to add structural support and return rigidity to thefragment 700 in the vicinity of the cavity 802. The additionalstructural reinforcement is advantageous because of the reducedthickness and reduced structural strength of the fragment 700 in thevicinity of the holes 704, and because of the further reduction instrength caused by the holes 704 themselves.

In view of the teachings herein, it will also be understood that atransparent or translucent structural reinforcing element, like thestructural plug 1402, may be used to reinforce any portion of alight-transmissive display pattern, such as an indicator or logo area,of the present invention, whether or not a cavity such as the cavity 802is present. This could be advantageous, for example, for a large logowherein such a large number of the holes 704 would be formed that thestructural integrity of the area would be reduced even in the absence ofthe cavity 802.

Referring now to FIG. 15, therein is shown the structure of the fragment700 in FIG. 13 provided with individual lights 1502, one for each of theholes 704, rather than the light 1302 (FIG. 13) that was common to allthe holes 704. The individual lights 1502 are depictedrepresentationally, it being intended and understood that the individuallights 1502 may be provided in a medium that is either discrete orcontinuous according to the particular application and needs at hand.Thus the individual lights 1502 may be, for example, individuallight-emitting diodes (“LEDs”), light sources from a discrete orcontinuous organic light-emitting diode (“OLED”) structure, or otherindividual light sources or emitters in discrete or continuous media asappropriate.

The individual lights 1502 can be individually controlled, for exampleby a CPU 1504 or other suitable controller responding in known fashionto appropriate programming or user input. Thus, it is possible to pairthe holes 704 with corresponding individual lights 1502 to formindividually controllable pixels. When aggregated together, theseindividual hole-light pixels form a controllable and changeable display.In this manner, by matching the pixel pitch (i.e., position and spacing)of the individual lights 1502 with the micro-perforated pattern of theholes 704, an invisible, programmable display can be made to appearthrough an apparently solid surface such as the opaque outer surface702.

The individual lights 1502 are thus light sources that are configuredand oriented behind the opaque outer surface 702 (metallic, plastic,coated, or otherwise) and are respectively aligned with the invisibleholes 704. The holes 704 in this embodiment are invisible. Theindividual lights 1502 are then configured to controllably shinepredetermined patterns of monochrome or multi-colored light through theinvisible holes to cause the holes 704 to function as pixels to providea controllable visual display through the seemingly solid surface. Byvirtue of the CPU 1504 (or other suitable mechanism) it is also possibleto then choose and customize aesthetic and display motifs by selectingand controlling the light and light patterns that are displayed throughthe invisible holes 704.

It will now also be clear to one of ordinary skill in the art that theseteachings may be combined as desired, such that, for example, a singleor a number of monochrome or multi-colored light sources may be used toprovide a visual display by shining the light through a selectivelytransmissive matrix. For example, the light may be shined through aliquid crystal display (“LCD”) or a thin film transistor (“TFT”) displayhaving pixels aligned with respective individual invisible holes such asthe holes 704.

Referring now to FIG. 16, therein is shown such a combined configuration1600. In this embodiment, a light source 1302 is positioned behind a TFTlayer 1602. The individual pixels 1604 of the TFT layer 1602 are alignedwith respective individual holes 704 to selectively and controllablyshine predetermined patterns of monochrome or multi-colored lightthrough the holes 704, as desired. From the perspective of the holes704, each of the individual pixels 1604 is configured as a light sourcealigned with its respective corresponding hole 704. In the aggregate,therefore, patterns of monochrome or multicolored light can becontrollably shined through the holes 704 to cause the holes 704 tofunction as pixels to provide a controllable visual display.

It will also now be clear that the holes 704 can be utilizedbi-directionally for receiving light as well as transmitting it. Thus,for example, the individual lights 1502 (FIG. 15) or the TFT layer 1602,for example, may also be configured to detect as well as transmit light,or even just to detect light. Such light detectors may serve, forexample, for receiving external control inputs for a processor,controller, or other device, such as the CPU 1504 (FIG. 15).

It has been unexpectedly discovered that the invisible,light-transmissive display system of the present invention providesexceptional versatility and choice in the presentation of displays. Forexample, in order to make the displays virtually invisible when thestatus indicators are in the off status, as illustrated for example inFIGS. 2B, 3B, and 4B, various surface effects and/or filler effects canbe employed. That is, for example, with a smoothly polished (e.g.,mirror finished) opaque outer surface 702 (such as illustrated in FIG.7), the presence of the invisible holes 704 (but not the holesthemselves) can sometimes be noticed because the holes will be slightlyless reflective. The holes 704 will therefore cause such a polishedsurface to appear slightly duller where the holes are located eventhough the holes themselves are not visible.

One way to compensate for the slightly less reflective properties of theholes, according to the present invention, is to provide a texturedsurface rather than smoothly polished surface (as also illustrated inFIG. 7). The surface may be textured such as by burnishing, etching,sandblasting, anodizing, engraving, and so forth. When the microtextureof the surface is made irregular in this manner, the invisible holes 704tend to blend in—that is, they get “lost” in the visual noise of thesurface texture. The rougher the texture depth, the more likely thepattern 706 of the invisible holes 704 will get lost within that texturewhen unilluminated.

In one embodiment, for example, having a surface roughness of 1.8 RA,the surface texture has peaks and valleys that have 30-40 11 m ranges inthem. So a 30 11 m hole, such as the invisible hole 704 at the outersurface 702, blends in nicely within a peak and a valley of 30 11 m.Thus there is no “surface blemish” that might otherwise be seen from theaggregation of the holes 704 that form the pattern 706, inasmuch as thesurface texture is substantially as large as the hole sizes at thattextured surface. In another embodiment, the aggregate presence of theinvisible holes 704 can be further disguised by darkening the surfacefinish slightly, such as by anodization, to provide, for example, abluish or grayish cast.

It will also be understood and appreciated by those of ordinary skill inthe art, based on this disclosure, that the hole spacings and sizes neednot be as uniform as they are illustrated in the above drawing FIGS.Variable spacings, sizes, and shapes may be used to achieve effects,such as differences in texture, gradations in brightness, and so forth.Hole patterns, angles, and pitch (spacings) can be varied and adjustedto avoid pointilization (i.e., pixilation), hot spots, and so forth,and/or to achieve desired effects, such as pointilization, hot spots,and so forth. Light distribution aides, such as light diffusers, canalso be used behind the invisible holes 704, as may be beneficial incertain circumstances.

Referring now to FIG. 17, therein is shown an embodiment 1700 of thepresent invention incorporating invisible holes 1702 that are outwardlydirected or tilted away from the central axis of the pattern 706. Thisprovides a wider viewing angle above the outer surface 702 by dispersingthe light from light 1302 over a wider angle.

Embodiment 1700 also illustrates another aspect of the presentinvention. The holes 1702 are not formed as symmetrical cones about anaxis normal to the outer surface 702 and to the rear surface 804.Instead, the shape of the cones has been offset at an outward angle,thus providing an angled hole shape having a principle axis that directsthe light outwardly.

\The shape of the holes 1702 is readily formed by the laser 902 (FIG. 9)by controlling the laser 902 to trepan the holes 1702 asymmetrically, asshown. Similarly, other invisible hole shapes can be formed, such asoval holes, oval and/or flattened cones, and so forth, bycorrespondingly controlling the trepanning orbits of the laser beam 904to achieve the desired hole shapes and profiles. It has beenunexpectedly discovered, in fact, that trepanning in this manner can beparticularly advantageous because angled holes can be thus achievedwithout having to change the angle of the laser 902 itself. The patterns706 can thus be customized with individual invisible holes each tailoredas desired without having to alter the angular setting of the laser 902for each such hole.

Referring now to FIG. 18, therein is shown an embodiment 1800 havinginvisible holes 1802 that are inwardly directed or tilted toward thecentral axis of the pattern 706. The embodiment 1800 thus illustratesanother configuration for customizing the invisible holes according tothe desired uses and applications. In this case, the invisible holes1802 can be angled to narrow the viewing angle, thereby providing a moreprivate viewing experience, for example. The invisible holes 1802 couldalso, for example, be aimed at a common point or region above the outersurface 702 to provide a visual “hot spot” at which the pattern 706 isparticularly brilliant to the viewer. This could be used advantageously,for example, to guide a viewer to a preferred viewing position and/ordistance.

Referring now to FIG. 19, therein is shown an embodiment 1900 having alight sensitive receptor 1902 behind the invisible holes 704, beneaththe rear surface 804 of the fragment 700, and configured for sensinglight through the invisible light-transmissive holes 704. The lightsensitive receptor 1902 may be sensitive to visible light to provideambient light sensing (“ALS”), for example, and/or sensitive toinfra-red (“IR”) light to receive IR control signals from a remotecontrol transmitter, for example. It will also be understood andappreciated now by those of ordinary skill in the art, based on thepresent disclosure, that in fact any appropriate light-sensitivefunction can be supported by a corresponding and appropriate lightsensitive receptor 1902, all without a visible blemish or “window” onthe outer surface 702.

Referring now to FIG. 20, therein is shown an embodiment 2000 configuredas an invisible proximity detector. For example, the light sensitivereceptor 1902 may be sensitive to IR in a manner similar to conventionalmotion detectors. Motion, such as motion of a person 2002, in thevicinity of the pattern 706 will then be detected and may be utilized asdesired, such as, for example to turn a device on, to play a greeting,to turn the device off or put it to sleep (e.g., when no one isdetected), and so forth. To improve the range of sensitivity, anoutwardly angled hole pattern is used such as illustrated in FIG. 17.

Referring now to FIG. 21, therein is shown an embodiment 2100 configuredas an invisible button. To focus the sensitivity to a small regionimmediately above the pattern 706, an inwardly angled hole pattern isused such as illustrated in FIG. 18. Then, whenever a finger 2102 ispositioned immediately thereabove, the light sensitive receptor 1902,which may be similarly selected to be sensitive to IR, detects thepresence of the finger 2102 for generating a suitable signal the same asif a conventional button had been pressed. However in this case, thebutton is not visible, according to the present invention, but insteadthe embodiment 2100 provides button emulation.

Referring now to FIG. 22, therein is shown a view similar to FIG. 7 of apattern 706 that is a variation upon the previously described shapes ofinvisible holes. In this embodiment, the hole has been elongatedtransversely into an invisible slot 2202, it being understood that theterm “slot” is thus used and defined in its usual sense to mean anopening that is longer in one dimension than in the transversedimension. It will be understood that the invisible slot 2202 may thenbe filled, if desired, for example with the clear coat 1202 (not shown)similarly as the invisible holes 704. The invisible slot 2202 may alsobe combined with other invisible slots and/or invisible holes of variousshapes, patterns, and dimensions, according to the present invention, asmay be desired or advantageous.

Referring now to FIG. 23, therein is shown a cross-sectional view of theinvisible slot 2202 taken on line 23-23 in FIG. 22.

Referring now to FIG. 24, therein is shown a cross-sectional view of theinvisible slot 2202 taken on line 24-24 in FIG. 22, and showing thetapered cross-sectional profile of the invisible slot 2202, similar tothe taper of the invisible holes 704 (FIG. 8), the slot taper beingformable in like manner to that of the holes.

Referring now to FIG. 25, therein is shown a flow chart of a process2500 for manufacturing an invisible, light-transmissive display system2500 in accordance with an embodiment of the present invention. Theprocess 2500 includes providing a light resistant material in a block2502; and penetrating substantially invisible, tapered,light-transmissive holes in a light-transmissive pattern through atleast a portion of the light resistant material using a laser beamhaving a focal width less than the smallest diameter of the taperedholes in a block 2504.

It has been discovered that the present invention thus has numerousaspects.

A principle aspect that has been unexpectedly discovered is that thesystem of the present invention can economically and unobtrusivelyprovide highly effective, aesthetically pleasing, and highly desirablesurface displays that can be made invisible when not activated.

Another aspect is that the system of the present invention can providefor light emanation from an apparently solid surface, with or without anintrinsic, visible design in that surface area.

Another aspect is that the system of the present invention closes andseals off the invisible holes, protecting and securing them and theouter surface from ingress of contaminants.

Another aspect is that the system of the present invention provides fora smooth and continuous surface, free from visible breaks and breaklines in the material.

Another aspect is that the system of the present invention provides forIR remote control through a light resistant surface, such as metal,without requiring a traditional window.

Another aspect is that the system of the present invention can be usedwith many types of light resistant materials, such as steel, plastic,ceramics, and so forth, in addition to aluminum.

Another aspect is that the system of the present invention makes theelements of the display (the micro-perforations that form the invisibleholes) small enough that they are not readily perceivable.

Another important aspect is that the system of the present inventionenables hardly perceivable and unperceivable windows (e.g., arrays ofthe invisible holes) to be put into materials, such as metal, thatordinarily require separate and readily visible breaches in the surfacesthereof.

Another aspect is that the system of the present invention successfullyprovides and enables an invisible light pipe through otherwise solidmaterials such as metal.

Another important aspect is that the system of the present invention canbe utilized with great success and effect with materials as describedabove that are not entirely opaque. Thus, invisible, light-transmissivedisplay systems can be provided for viewing at an outer surface, notonly of substantially opaque materials, but also of materials that arenot opaque. A light resistant material that nevertheless allows somelight to pass through, such as a translucent colored plastic, canfurnish the basis for very dramatic display systems according to thepresent invention. Thus, in view of the teachings herein, it will now beclear to one of ordinary skill in the art that the invisible holes andsystems according to the present invention, penetrated in a desiredlight-transmissive display pattern through at least a portion of lightresistant material, will cause much brighter (and pleasingly unexpected)display patterns than if shined through materials that lack the presentinvention.

Another aspect is that the system of the present invention can be usedfor an extensive variety of desired displays, such as informationalpatterns, logos, control indication patterns, status indicationpatterns, directive patterns, artistic patterns, and so forth.

Yet another aspect is that the system of the present invention makes itpossible to provide for and to enable the user to choose and thuscustomize aesthetic and display motifs according to individualpreferences, by selecting and controlling the light and light patternsthat are displayed through the invisible holes.

Another aspect is that the system of the present invention can provideselectable illumination through visible and otherwise apparently soliddisplays, designs, patterns, indicators, logos, and so forth.

Another aspect is that the system of the present invention can be usedwith virtually any kind of device needing or benefiting from anilluminated display configuration, such as computers, display panels,personal data assistants, personal music players, applianceinstrumentation, vehicle instrumentation, a vehicle display, electronicsinstrumentation or display, jewelry, interactive kiosks, automatedtellers, communication devices (such as cell phones, wired and wirelesstelephones, walkie-talkies, etc.), remote control devices, medicalinstruments or devices, training simulators, and so forth.

Another aspect is that the present invention allows displays to beprovided in a fully metallic surface, thereby reducing vulnerability andimproving the durability and robustness thereof.

Yet another important aspect of the system of the present invention isthat it valuably supports and services the historical trend of reducingcosts, simplifying systems, and increasing performance.

These and other valuable aspects of the present invention consequentlyfurther the state of the technology to at least the next level.

Thus, it has been discovered that the invisible, light-transmissivedisplay system of the present invention furnishes important andheretofore unknown and unavailable solutions, capabilities, andfunctional aspects for display systems for electronic and other devices.The resulting configurations are straightforward, cost-effective,uncomplicated, aesthetically pleasing and attractive, highly versatileand effective, can be surprisingly and unobviously implemented byadapting known technologies, and are thus readily suited for efficientlyand economically manufacturing highly desirable and appealing invisibledisplay systems.

While the invention has been described in conjunction with a specificbest mode, it is to be understood that many alternatives, modifications,and variations will be apparent to those skilled in the art in light ofthe aforegoing description. Accordingly, it is intended to embrace allsuch alternatives, modifications, and variations that fall within thescope of the included claims. All matters hithertofore set forth hereinor shown in the accompanying drawings are to be interpreted in anillustrative and non-limiting sense.

What is claimed is:
 1. An electronic device comprising: a housing havinga first surface and a second surface and having at least a one holeformed through the housing between the first surface and the secondsurface, wherein the at least one hole is less than 0.1 mm in diameterat the first surface and wherein the cross-sectional area of the atleast one hole increases as the hole extends from the first surface tothe second surface; and a light sensitive receptor positioned adjacentthe second surface proximate the at least one hole.
 2. The electronicdevice of claim 1, wherein the first surface is opaque.
 3. Theelectronic device of claim 1, wherein the at least one hole is tapered.4. The electronic device of claim 1, wherein the at least one hole isconical.
 5. The electronic device of claim 1, wherein the at least onehole is less than 0.04 mm in diameter.
 6. The electronic device of claim1, wherein the housing comprises a plurality of holes formed through thehousing between the first surface and the second surface, the pluralityof holes being clustered together to form a pattern, wherein each of theplurality of holes is less than 0.1 mm in diameter at the first surfaceand wherein the cross-sectional area of each of the plurality of holesincreases as the respective hole extends from the first surface to thesecond surface.
 7. The electronic device of claim 6, wherein the patternhas an approximate center and wherein at least a portion of theplurality of holes are tilted outwardly with respect to a longitudinalaxis that passes through the approximate center substantiallyperpendicular to the first surface.
 8. The electronic device of claim 6,wherein the pattern has an approximate center and wherein at least aportion of the plurality of holes are tilted away from a longitudinalaxis that passes through the approximate center substantiallyperpendicular to the first surface.
 9. The electronic device of claim 8,wherein at least the portion of the plurality of holes tilted away fromthe longitudinal axis are tilted toward a preferred viewing position ofa user of the electronic device.
 10. The electronic device of claim 1,wherein the first surface comprises a texture with peaks and valleysthat range in size at least as large as the diameter of the at least oneopening.
 11. The electronic device of claim 1, comprising alight-conductive filler in the at least hole.
 12. The electronic deviceof claim 1, comprising control circuitry coupled to the light sensitivereceptor to generate a signal correlative to ambient light sensed by thelight sensitive receptor.
 13. The electronic device of claim 1,comprising control circuitry coupled to the light sensitive receptor togenerate a signal correlative to infrared light sensed by the lightsensitive receptor.
 14. The electronic device of claim 1, wherein thelight sensitive receptor comprises a proximity detector.
 15. Anelectronic device comprising: a housing configured to hold a keyboard,wherein the keyboard includes a plurality of keys, at least one of theplurality of keys having a first surface and a second surface and havingat a plurality of holes formed between the first surface and the secondsurface to create a pattern of holes, wherein each of the plurality ofholes is less than 0.1 mm in diameter at the first surface and whereinthe cross-sectional area of each of the plurality of holes increases asthe hole extends from the first surface to the second surface; and alight source positioned adjacent the second surface proximate thepattern of holes, such that the pattern of holes is substantiallyinvisible when the light source is off and such that the light sourceilluminates the pattern of holes when the light source is on.
 16. Theelectronic device of claim 15, wherein the pattern of holes comprises astatus indicator.
 17. The electronic device of claim 16, wherein thestatus indicator comprises a caps lock indicator.
 18. The electronicdevice of claim 16, wherein the status indicator comprises a sleepindicator.
 19. An electronic device comprising: a housing configured tohold a battery, the housing having a first surface and a second surfaceand having at a plurality of holes formed between the first surface andthe second surface to create a pattern of holes, wherein each of theplurality of holes is less than 0.1 mm in diameter at the first surfaceand wherein the cross-sectional area of each of the plurality of holesincreases as the hole extends from the first surface to the secondsurface; and a light source positioned adjacent the second surfaceproximate the pattern of holes, such that the pattern of holes issubstantially invisible when the light source is off and such that thelight source illuminates the pattern of holes when the light source ison to provide an indication of the battery's state of charge.
 20. Theelectronic device of claim 19, wherein the pattern of holes comprises aplurality of circular patterns and wherein more of the plurality ofcircular patterns are illuminated by the light source as the battery'sstate of charge increases.